Somewhere mid-20th century a German nun (dasa-sil-mata in Srilankan parlance) undertook a voyage to Sarnath, the place where Buddha spoke his First Sermon, that is, his first official sermon. Impressed by the story of his life, and educated in translatory work Sister Vajira put herself to translating the Maha-parinibbana Sutta, the Teaching (sutta) on the last days of Buddha, how he died, how he spoke in the weeks prior to this event, and what happened afterwards.
The Maha-parinibbana Sutta is one of the texts that appears in the Pali Dīgha Nikaya, the Compendium (nikáya) containing the Longer (dīgha) Teachings.
Sister Vajira’s efforts have been put online by Thaníssaro bhikkhu (a bhikkhu is a fully ordained monk in the theravāda-tradition).
He provided a number of footnotes on difficult technical terms, but omitted a lemma on the “esoteric and exoteric” as Vajira — and by the way, a number of other translators among whom the Srilankan monk Pategáma Ñana-ráma — gave it.
In Vajira’s words the passage containing “esoteric and exoteric” runs as follows:
“Thus spoke the Venerable Ānanda, but the Blessed One answered him, saying: “What more does the community of bhikkhus expect from me, Ānanda? I have set forth the Dhamma without making any distinction of esoteric and exoteric doctrine; there is nothing, Ānanda, with regard to the teachings that the Tathágata holds to the last with the closed fist of a teacher who keeps some things back.”
The Pali text runs as follows:
Desito Ānanda mayā dhammo anantaram abāhiram karitvā natthi
Ānanda tathāgatassa dhammesu acariyamutthi.
Anàntaram (my emphasis on the à) means “without end, exhaustive”.
Abāhiram must be interpreted in the sense of “the interior and the exterior”.
Therefore Buddha says that he taught his monks all there is to know about what goes on in our own body-mind complex, and he says that he taugt all there is to know about the world outside our body-mind complex.
To translate Abāhiram and the rest with the abbreviation “esoteric and exoteric” is totally besides the subject, especially when remembering that the Pali (= theravāda) tradition explicitely denies that Buddhism has anything esoteric, anything that could be called a hidden teaching or a concealed practice. To illustrate this point of view they cite the same given passage where Buddha says: “… there is nothing, Ānanda, with regard to the teachings that the Tathágata holds to the last with the closed fist of a teacher who keeps some things back.”